diff --git a/src/infra/approval-gateway-resolver.test.ts b/src/infra/approval-gateway-resolver.test.ts
index f9366208314..10e4666177a 100644
--- a/src/infra/approval-gateway-resolver.test.ts
+++ b/src/infra/approval-gateway-resolver.test.ts
@@ -11,7 +11,7 @@ vi.mock("../gateway/operator-approvals-client.js", () => ({
 }));
 
 function requireFirstMockCall<T>(mock: { mock: { calls: T[][] } }, label: string): T[] {
-  const call = mock.mock.calls.at(0);
+  const call = mock.mock.calls[0];
   if (!call) {
     throw new Error(`expected ${label} call`);
   }